The decline in fertility experienced by the industrialised economies over recent decades was for a long time attributed to the rising labour force participation of women. For instance, the authors of the concept of the second demographic transition ascribe the fall in the propensity to have children to the rising economic autonomy of women and their desire for self-fulfilment, among other things (Van de Kaa, 1988: 17; Lesthaeghe, 1992). The delegates at the UN Population Conference in Sofia in 1983 came to a similar conclusion (UN 1983 after Willekens, 1991).